1. Field of the Invention
The present invention relates to a rotation switch and an electronic timepiece.
2. Description of the Related Art
An electronic wristwatch, for example, is configured such that the stem is pulled outward to a predetermined position and rotated so that the hands thereof move corresponding to the rotation of the stem for time adjustment. As a time adjusting device for an electronic wristwatch such as this, a device configured as described in United States Patent Application. Publication No. 2008/0112275 is known in which the wristwatch case is provided with a stem that is movable to a first position and a second position in an axial direction thereof and rotatable in the direction of rotation around the axis of the stem, and magnetic sensors positioned in the circumferential direction of magnets provided in the stem are provided inside the wristwatch case.
In this type of electronic wristwatch, when the stem is pressed inward to the first position, the magnet provided on the stem separates from the magnetic sensor. Conversely, when the stem is pulled outward to the second position, the magnet moves with the stem and faces the magnetic sensor. Subsequently, when the stem is rotated in this position, the magnet rotates with the stem, and the magnetic field of the rotating magnet is detected by the magnetic sensor. Then, based on this detection data detected by the magnetic sensor, the hands are moved, and as a result, the time is adjusted.
However, a conventional electronic wristwatch such as this is structured such that, when the stem is pulled outward to the second position so that the magnet moves with the stem and faces the magnetic sensor, the magnetic sensor is merely placed near the magnet of the stem. Therefore, the magnetic sensor is easily affected by magnetic fields outside of the wristwatch, which possibly leads to malfunction.
Additionally, in a conventional electronic wristwatch such as this, the magnet is designed larger as a technique for increasing the sensitivity of the magnetic sensor. However, there is a problem in that, when the magnet is designed larger, the thickness of the overall device increases, causing the increase of the overall device size.